A、C群脑膜炎奈瑟球菌免疫原性及毒性和传代稳定性研究

目的 为保证疫苗质量的一致性和可控性,对A、C群脑膜炎奈瑟球菌结合疫苗生产用菌株CMCC(B)29201和CMCC(B)29205株进行毒性和抗原传代稳定性研究,并对30代次菌进行脑腔毒性、免疫原性和产糖质量分析.方法 将A、C群脑膜炎奈瑟球菌工作种子批菌种分别连续传代至30代次并收获3、5、10、15、20、25及30代次菌液,小鼠腹腔注射观察各代次毒性,试管凝集试验和间接ELISA测定各代次抗原性.其中30代次菌液进行小鼠脑腔攻击观察是否引起脑组织病理改变,小鼠皮下免疫观察免疫原性,同时进行发酵培养提取荚膜多糖的质量分析.结果CMCC(B)29201株和CMCC(B)29205株工作种子批菌种的半数致死量(LD50)均≥109个/ml,30代次内的LD50也均≥109个/ml,30代次菌液脑腔毒性测定显示均无病理改变;抗原性试管凝集效价均达1∶320,30代次内的试管凝集效价均达1∶320,ELISA几何平均滴度(GMT)分别为1∶4835和1∶3915,且30代次内的ELISA效价分别为1∶4315和1∶3752以上;30代次菌液的血清杀菌抗体均≥1∶32,用第30代次工作种子批菌种生产的A群和C群脑膜炎奈瑟球菌荚膜多糖各项检定指标均达到国家标准.结论 A、C群脑膜炎奈瑟球菌结合疫苗生产用菌株CMCC(B)29201和CMCC(B)29205株毒性低、抗原性和免疫原性良好,连续传代至30代次仍保持较低的毒性和较好的抗原性及免疫原性,纯化的A群和C群脑膜炎奈瑟球菌荚膜多糖质量符合质控要求.

Study on the immunogenicity and the stability of the toxicity,antigenicity of Neisseria meningitidis serogroup A/C

Objective To study the stability of the toxicity,antigenicity and immunogenicity of Neisseria meningitidis serogroup A/CCMCC(B)29201/29205],and to analyze the quality of the capsular polysaecharide extracted from Neisseria meningitidis.Methods The toxicity of the 3rd,5th,10th,15th,20th,25th and 30th passage of the Neisseria meningitidis was assayed in mice,and the antigenicity of each passage was measured by the tube agglutination test(TAT)and ELISA.The effect of individual 30 passages of Neisseria nveningitidis on the brain tissue and the immunogenicity of each passage were tested in mice,and the capsular polysaccharide was purified and analyzed.Resuits The LD50 of the strains CMCC(B)29201/29205 of each passage was low(≥109/ml),and all the 30 passages of the two strains had no effect on the brain tissue of the mice.The titer of each passage was 1∶320 in TAT and more than 1∶3752 in ELISA.After immunization with individual 30 passages of the Neisseria meningitidis the titers in serum bactericidal assay (SBA)were all more than 1∶32.The capsular polysaccharide purified from Neisseria meningitidis met the quality standard of the requirement.Conclusion The strains of Neisseria meningitidis serogroup A/C used in the manufacture of the meningococcal conjugate vaccine,are stable in the toxicity,antigenicity and immunogenicity.And the capsular polysaccharide has met the quality standard.